ozjohn

Very nice. I found welding glasses very effective for photographing an eclipse. Perhaps not recommended but effective.

I like the Colonial bit probably Australia or S A colonies.

An orchid in my court yard. It was one brought from Costco which I attached to a small tree when it had finished flowering. If you keep them in pots they tend to die from over watering.

Did you use a telescope or a telephoto lens on your camera? In the past I have attached a digital camera to my X - Y 4" tracking telescope. and taken multiple photos of the object in question. As the X-Y tracking causes blurring of the picture there are SW packages (their name escapes me) that aligns the multiple images and building them up into a composite picture. They also contain all of the normal image processing, brightness, contrast, noise reduction, sharpening etc. A very nice picture of the moon.

I think you are right. An interaction between the scanning pixel size and the computer display size aliasing perhaps.

That's a very strange effect around the the Scottish lion? Overall a very nice fully struck obverse.

Some very nice 1910 halfcrowns.

It seems that the quality of strike for 1910 halfcrowns could be variable. Here's my 1910 halfcrown.. Firstly the reverse is a better strike than the obverse and I would grade it as UNC. The obverse is a weaker strike but given the reverse you have to cut some slack as both sides of the coin should wear evenly. As a result I would give an overall grade of gEF for the coin. In summary a very nice coin. I think I would prefer this coin to the PCGS example.

I noticed there is a video attached to the Ebay listing for this item showing the coin being examined. The coin looks much better in this video than the photos supplied in the listing. In the video you can see the edge of the coin quite clearly and that looks pretty good. Perhaps it is just a lightly struck coin. Like some of the replies say it looks better in the hand as it is hard to get a good picture when photographing through a plastic capsule. The PCGS photos don't help the coin either.

https://www.ebay.co.uk/itm/EDWARD-VII-1910-SILVER-HALFCROWN-PCGS-MS62/274304517864?hash=item3fddd2c6e8:g:d3gAAOSwvXReal8B I know I keep on banging on about TPGers but I have difficulty in a MS 62 grading for this coin by PCGS

A really nice obverse but weakness in Britannia's head on the reverse. It seems that getting a well struck obverse and reverse is elusive. This is my example not perfect but probably representative of the RM's output at the time.

Perhaps people liked the reverse George and Dragon design as it was reintroduced after a gap of several years on crowns The one on sovereigns was a bit small and not many people had sovereigns. Personally I quite like the jubilee effigy of the queen which also reflects the belle epoque period of the time

https://www.ebay.com/itm/1913-Great-Britain-Florin-2-SHILLINGS-KM-817-NGC-MS-62/322982118893?hash=item4b333c05ed:g:AuYAAOSwlPFeMxHD I don't think this one qualifies for a MS grading. There is a serious metal flaw on the obverse, signs of wear that cannot be explained by a weak strike, and many bag marks on both obverse and reverse. Below is scan of my example is included a coin I have had for many years and brought it at MR Roberts, Wynyard, I think it was less than $Au 50. IMO I think this coinis somewhere in the MS range.

I have a bag of .500 and .925 silver coins weighing close to 1kg taken from circulation. I'm sure lots of other people have hoarded them.

Either way changing history for ideological reasons or inadvertently or for personal gain is not a good thing. Museums are supposed to be a record of what happened.

Fortunatly not many people live in the area. Cyclones on the east coast are a different matter.

Or someone trying to rewrite history? I'm sure imperial connections are not encouraged by the present regime in SA.

I saw Alistair Campbell on a ABC program called Q&A which is a current affairs program with the panel and audience stacked against some hapless right wing politician who is stupid enough to appear on the program. Much of the content is focused on climate change. In this case Campbell was attacking Brexit , the world's about to end , economic ruin, the electorate are stupid etc. etc. without any justification for his views.

. . I appoligize for my initial scepticism but I guess that's the engineer coming out never accept anything on face value. I have to say your post was the first I have heard of thermoradiative cells and I have not seen anything so far from the renewable energy brigade in Australia. Thanks for alerting me. It seems that these theromradiative cells are like the QM equivalent of heat pump where a small amount of energy is expended by radiating it out to outer space and drawing a greater amount of energy from the environment which in turn gives electrons the energy to jump into the conduction band and become available as useable energy. I guess I was too tied up with the operation of conventional PV cells to see the difference. Thanks again for alerting me to this new technology.

If that were the case they wouldn't be attempting to reverse the action of PV cells as suggested in the article. The PV cells would be operating in the conventional mode as if they were facing the sun ie they receive a quanta of IR from the warm house which energizes an electron to jump into the conduction band and available to produce a potential across the PN junction of the PV cell. A PV cell receiving IR radiation from a hot surface would certainly generate electricity providing the doping of the semiconductor was consistent with the wavelength of the quanta of IR emitted from the warm house. but 50W/m^2 ? This very optimistic, also as the night cools so would the radiated power from the warm house reduce thus reducing the PV cells output further. When I read the article it seem to imply that the PV cell was radiating to outer space which has a temperature of 4 deg K ( absolute zero 0 deg K or -273 deg C) which by some unexplained process released energy up to 50w/m^2 in the reverse direction to a conventional PV cell. For this to happen the energy has to come from somewhere or someone has found a way of getting round the laws of physics which is unlikely. If this were the case perpetual motion machines would become a reality coal, gas , oil and nuclear would be redundant.

Redcliffe update. We've had a cool change today 26 degC max. with rain. Tomorrow's forcast 22 to 25 degC with rain, 100mm. Sea temp. 27 degC.

I looked at your reference and I am afraid I am sceptical .Conventional PV cells work by receiving a quanta of light energy which allows an electron to jump into the conduction band and become available as energy. Current PV cells have an efficiency of less than 25% with 30% the maximum which is set by quantum physics not engineering. For a current 1m^2 PV cell normal to the sun would receive about 800 W. and output about 200 W. In your anti PV cell reference it is suggesting that radiating from the cell to outer space energy can be generated. To start radiating energy to space this would represent a loss in energy to the system and each quanta of light emitted would require electrons to lose energy binding them more tightly to their parent atom making them less likely to be in the conduction band. In quantum mechanics never say never but the probability would be low. The reference does not attempt explain where the generated energy through the loss of energy comes from remembering that energy cannot be created or destroyed the fundamental law of thermodynamics. It has to come from somewhere your reference vaguely suggests that the PV cell process is reversed and this energy from nowhere is available in the opposite direction which is not convincing for the reasons given This one sounds like a perpetual motion machine.

Air conditioning is good but expensive to run. We run the air conditioning in the day as we have roof top solar PV cells At night we have ceiling mounted fans which are good and cheap to run I would like to have lithium batteries such as a Tesla Powerwall as a backup at night and cloudy days but they are very expensive approx. $12000 and are not cost effective as they would not break even until after the warrantee period of 10 years had expired. Such is the drawback with renewables they cannot deliver a reliable supply without some form of backup. I don't think anyone has thought too much about the disposal/recycling of lithium batteries which contain lithium which is a very reactive metal.

Beautiful one dayday perfect the next is what they say about Queensland. Don't mention the cyclones and bushfires.

Sorry F+/F